解决国内访问github速度慢的问题

从简书中转载：

https://www.jianshu.com/p/66facbd8926a

由于某些原因，国内访问github会异常缓慢，在clone仓库时甚至只有10k一下的速度，下载半天也下不完。

本文介绍通过修改系统hosts文件的棒啊，绕过国内dns解析，直接访问github的cdn节点，从而达到加速的目的。

1.进入github官方cdn地址

https://www.ipaddress.com/

2.查询下面两个连接的dns解析地址

github.com

github.global.ssl.fastly.net

3.修改系统hosts文件

打开系统hosts文件（管理员权限）

windows路径：C:WindowsSystem32driversetc

mac打开方式 sudo vim /etc/hosts

在末尾添加三行记录并保存。注意ip地址与域名间需要有空格

# Copyright (c) 1993-2009 Microsoft Corp.
#
# This is a sample HOSTS file used by Microsoft TCP/IP for Windows.
#
# This file contains the mappings of IP addresses to host names. Each
# entry should be kept on an individual line. The IP address should
# be placed in the first column followed by the corresponding host name.
# The IP address and the host name should be separated by at least one
# space.
#
# Additionally, comments (such as these) may be inserted on individual
# lines or following the machine name denoted by a '#' symbol.
#
# For example:
#
#      102.54.94.97     rhino.acme.com          # source server
#       38.25.63.10     x.acme.com              # x client host

# localhost name resolution is handled within DNS itself.
#   127.0.0.1       localhost
#   ::1             localhost

192.30.253.112     github.com

199.232.69.194    github.global.ssl.fastly.net

4.刷新系统dns缓存

windows：

Windows + X 打开系统命令行（管理员身份）或者 powershell

运行 ipconfig /flushdns 手动刷新系统dns缓存

mac：

sudo killall -HUP mDNSResponder

5.大功告成